Experimental study of chamber rockburst based on displacement field evolution

To study the characteristics of chamber rockburst,the mechanics mechanism of chamber rockburst was investigated based on the experimental studies of surrounding rock deformation evolution field.In the experiment,a sandstone rock board with chamber was compressed using biaxial loading mode.Using the white light digital speckle correlation method as an experimental monitoring method,the displacement field and strain field in the process of deformation and failure were monitored in real-time.According to the analysis of experiment,the process of chamber rockburst goes through two stages: local damage of surrounding rockmass and the structural instability and failure.Also,the mechanical mechanism of rockburst shows that the chamber rockburst is caused by the combined actions of stretching and shearing.